An epr nuclear power unit accident initiating event list optimization method and system

Abstract

The present application relates to a kind of EPR nuclear power unit accident initiation event list optimization method and system, method includes: collecting the initiation event list of each nuclear power unit;Each initiation event list is compared and analyzed, and the optimization object of the accident initiation event list of EPR nuclear power unit is determined according to comparison result;Frequency analysis is carried out to the accident initiation event in optimization object;EPR accident classification standard and frequency analysis result are combined to reclassify accident;According to the classification result, optimization initiation event list is carried out;Generation optimized initiation event list.Through implementation of the present application, after the optimization of the accident initiation event list of EPR nuclear power unit, optimization EPR accident analysis and EPR nuclear power unit operation technical specification are carried out, realize unit online maintenance, further improve the economic benefit of nuclear power plant under the premise of guaranteeing safety.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of nuclear power unit initiating event analysis, and particularly relates to an EPR nuclear power unit accident initiating event list optimization method and system. BACKGROUND

[0002] The VVER nuclear power unit designed for four safety systems can realize online maintenance of one safety system, and effectively reduce the workload in overhaul.

[0003] According to the current preparation principle of the EPR operation technical specification, the final safety analysis report (FSAR) of the nuclear power plant provides the overall input of safety requirements for the preparation of the operation technical specification. Therefore, in order to improve the flexibility of unit operation and realize online maintenance of more system equipment to shorten the overhaul period, it is necessary to conduct in-depth comparison, analysis and research on the FSAR accident analysis of EPR, further clarify the relationship between accident analysis and EPR operation technical specification preparation, optimize the operation technical specification preparation methodology, and realize online maintenance to improve the performance level of the power plant. SUMMARY

[0004] The technical problem to be solved by the present application is that, according to the optimized initiating event list, the EPR accident analysis and the EPR nuclear power unit operation technical specification are optimized, and an EPR nuclear power unit accident initiating event list optimization method and system are provided.

[0005] The technical solution adopted by the present application to solve the technical problem is: providing an EPR nuclear power unit accident initiating event list optimization method, comprising the following steps:

[0006] Step S10: collecting initiating event lists of each nuclear power unit;

[0007] Step S20: comparing and analyzing each of the initiating event lists, and determining the optimization object of the EPR nuclear power unit accident initiating event list according to the comparison result;

[0008] Step S30: performing frequency analysis on the accident initiating event in the optimization object;

[0009] Step S40: reclassifying the accident in combination with the EPR accident classification standard and the frequency analysis result;

[0010] Step S50: optimizing the initiating event list according to the classification result;

[0011] Step S60: generating the optimized initiating event list.

[0012] Preferably, the step S10 further comprises:

[0013] obtaining a design safety requirement of an EPR nuclear power unit;

[0014] The step S20 further comprises:

[0015] dividing an operation range of the EPR nuclear power unit into a plurality of states according to the design safety requirement, transversely comparing a list of initiating events of the EPR nuclear power unit with a list of initiating events of other nuclear power units, identifying difference items between the lists of initiating events, and selecting a corresponding initiating event from the plurality of states as an optimization object of the list of accident initiating events according to the identification result.

[0016] Preferably, the accidents include unisolable loss of coolant accidents and isolable loss of coolant accidents.

[0017] The step S30 comprises:

[0018] performing frequency analysis on the unisolable loss of coolant accidents and the isolable loss of coolant accidents in the corresponding initiating event, and obtaining the frequency analysis result of the corresponding initiating event.

[0019] Preferably, the unisolable loss of coolant accidents include reactor coolant system pipe rupture and pressurizer safety valve stuck open.

[0020] The isolable loss of coolant accidents include in-containment residual heat removal system pipe break and out-of-containment residual heat removal system pipe break.

[0021] Preferably, the step S20 further comprises:

[0022] Step S21: analyzing a frequency source of the accident initiating event in the optimization object, and when it is judged that the frequency source does not conform to a preset standard, performing the step S30.

[0023] Preferably, the frequency source includes in-containment unisolable small break accident and out-of-containment isolable residual heat removal system break.

[0024] The application also constructs an EPR nuclear power unit accident initiating event list optimization system, comprising:

[0025] An acquisition module is configured to acquire a list of initiating events of each nuclear power unit.

[0026] A comparison module is configured to compare and analyze each list of initiating events, and determine an optimization object of an EPR nuclear power unit accident initiating event list according to a comparison result.

[0027] A frequency analysis module is configured to perform frequency analysis on the accident initiating event in the optimization object.

[0028] a classification module configured to reclassify the accident in combination with the EPR accident classification standard and the frequency analysis result;

[0029] an optimization module configured to optimize the initiating event list according to the classification result;

[0030] a result generation module configured to generate the optimized initiating event list.

[0031] Preferably, the collection module is further configured to:

[0032] obtain design safety requirements of the EPR nuclear power unit;

[0033] the comparison module is further configured to:

[0034] divide the operation range of the EPR nuclear power unit into a plurality of states according to the design safety requirements, compare the initiating event list of the EPR nuclear power unit with the initiating event lists of other nuclear power units, identify difference items between the initiating event lists, and select corresponding initiating events from the plurality of states as optimization objects of the accident initiating event list according to the identification result.

[0035] The application also provides an electronic device, which comprises:

[0036] one or more processors;

[0037] a storage device configured to store one or more programs, which, when executed by the one or more processors, cause the one or more processors to implement the EPR nuclear power unit accident initiating event list optimization method according to any one of the above.

[0038] The application also provides a storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the EPR nuclear power unit accident initiating event list optimization method according to any one of the above.

[0039] By implementing the application, the following beneficial effects are achieved:

[0040] The application discloses an EPR nuclear power unit accident initiating event list optimization method and system, and the method comprises the following steps: comparing the differences between the EPR nuclear power unit and other nuclear power units, determining the optimization object of the accident initiating event list, analyzing the accident initiating event frequency to obtain the frequency analysis result, reclassifying the accidents according to the EPR accident classification standard and the frequency analysis result, and finally optimizing the initiating event list according to the classification result to obtain the optimized initiating event list. After the initiating event list of the EPR nuclear power unit is optimized by the method, the EPR accident analysis and the EPR nuclear power unit operation technical specification are optimized, the unit online maintenance is realized, and the economic benefits of the nuclear power plant are further improved under the premise of ensuring safety. BRIEF DESCRIPTION OF DRAWINGS

[0041] The application will be further described below in combination with the drawings and embodiments, and the drawings are as follows:

[0042] Figure 1 is a flowchart of the EPR nuclear power unit accident initiating event list optimization method of the application;

[0043] Figure 2 is a flowchart of the frequency calculation of the stable voltage regulator safety valve jamming;

[0044] Figure 3 is a module block diagram of the EPR nuclear power unit accident initiating event list optimization system of the application. DETAILED DESCRIPTION

[0045] In order to have a clearer understanding of the technical features, objects and effects of the application, the specific embodiments of the application will be described in detail with reference to the drawings.

[0046] It should be noted that the flowchart shown in the drawings is only illustrative, and does not necessarily include all the contents and operations / steps, nor does it necessarily execute in the order described. For example, some operations / steps can be further divided, and some operations / steps can be combined or partially combined, so that the actual execution order may be changed according to the actual situation.

[0047] The block diagram shown in the drawings is only a functional entity, and does not necessarily correspond to a physically independent entity. That is, the functional entities can be realized in the form of software, or realized in one or more hardware modules or integrated circuits, or realized in different networks and / or processor devices and / or microcontroller devices.

[0048] Among them, the abbreviations and key terms of the application are defined as follows:

[0049] DBC: design basis conditions; DEC: design extension conditions; EPR: European pressurized reactor; FSAR: final safety analysis report; PWR: pressurized water reactor; LOCA: loss of coolant accident; RCP: reactor coolant system; RCV: reactor and containment control system; RHR: residual heat removal system; RIS: safety injection system.

[0050] In the embodiment, as shown in the figure, Figure 1 The application provides an EPR nuclear power unit accident initiating event list optimization method, which comprises the following steps:

[0051] Step S10: collecting initiating event lists of nuclear power units;

[0052] Step S20: comparing and analyzing the initiating event lists, and determining optimization objects of the EPR nuclear power unit accident initiating event list according to the comparison results;

[0053] Step S30: performing frequency analysis on the accident initiating events in the optimization objects;

[0054] Step S40: reclassifying the accidents in combination with the EPR accident classification standard and the frequency analysis results;

[0055] Step S50: optimizing the initiating event list according to the classification results;

[0056] Step S60: generating the optimized initiating event list.

[0057] Specifically,

[0058] In the embodiment, step S10 further comprises:

[0059] obtaining design safety requirements of the EPR nuclear power unit;

[0060] Step S20 further comprises:

[0061] dividing the operation range of the EPR nuclear power unit into multiple states according to the design safety requirements, comparing the initiating event list of the EPR nuclear power unit with the initiating event lists of other nuclear power units horizontally, identifying difference items between the initiating event lists, and selecting corresponding initiating events from the multiple states as the optimization objects of the accident initiating event list according to the identification results.

[0062] In the reactor probabilistic safety analysis, the initiating event is defined as a disturbance occurring in the reactor, which may potentially cause reactor core damage. At present, the third generation pressurized water reactor nuclear power units at home and abroad mainly include AP1000, EPR and Hualong No. 1, etc. The initiating event lists of the three types of nuclear power units are different, and the differences between the EPR nuclear power unit and other third generation units and pressurized water reactor nuclear power plants need to be determined through data analysis.

[0063] The main information to be collected includes: EPR design safety requirements, AP1000 initiating event list, Hualong No. 1 nuclear power unit initiating event list, international general data source of initiating event frequency, safety analysis of shutdown condition of pressurized water reactor nuclear power plant, and pipe failure frequency of commercial nuclear power plant.

[0064] In this embodiment, the EPR unit operating range is divided into states A, B, C, D, E and F according to the EPR design safety requirements. The specific division of the six states is shown in Table 1.

[0065] Table 1: EPR nuclear power unit operating range

[0066]

[0067]

[0068] By analyzing the upstream design source of the EPR unit initiating event analysis (French regulations or regulatory requirements), the design requirements of the newly added initiating events (including spent fuel pool related accidents) are determined, and are compared with the initiating events of AP1000, Hualong No. 1 and other nuclear power units, the differences in the initiating event list are identified, and the optimizing initiating event list is analyzed. The engineering judgment method is adopted, and the initiating event lists of domestic and foreign third-generation pressurized water reactors are referred to, such as the initiating event lists of EPR same type power plants (US EPR and Finland OL3 power plant), third-generation other power plants (Fuqing Hualong, AP1000), etc. The optimizing initiating event list is analyzed. The comparison and analysis results of the EPR nuclear power unit initiating event list and other type PWR nuclear power units are shown in Table 2.

[0069] Table 2: Comparison of EPR nuclear power unit initiating event list and other units

[0070]

[0071]

[0072] As can be seen from the comparison, the FSAR initiating event list of the EPR unit is more detailed than that of the Hualong unit and the AP1000 unit. Compared with the typical third-generation pressurized water reactor nuclear power unit, the EPR nuclear power unit adds small break LOCA (≤DN 50) under states C, D and E, including the break of the emergency boron injection pipeline; the break of the containment internal (external) residual heat removal system pipeline (isolatable) (≤DN 250) under states C, D and E; and the non-isolatable small break (<50mm) or isolatable RIS break (<250mm) of the spent fuel pool drainage under state E.

[0073] Compared with the core accident, the mechanism of the spent fuel pool accident is relatively simple, and the accident process is relatively slow. In the case of non-break and break accidents, when the spent fuel pool cooling is completely lost, the boiling and exposure of the spent fuel pool will last for a long time under different working conditions. Therefore, the identified spent fuel pool accident is not suitable for the analysis method given in the patent. Compared with other third-generation nuclear power plants, such as AP1000 and China's version of Hualong No. 1, no break accident is considered during shutdown. The small break accident of the low mode primary circuit and its connected pipeline of the EPR nuclear power unit and the high mode small break accident are all listed as design basis conditions. Compared with other third-generation nuclear power plants, the working condition classification is relatively strict, which is not conducive to the operation and maintenance management of the unit after commercial operation. Therefore, the LOCA accident under states C, D and E is taken as the optimization object.

[0074] By comparing with the list of typical pressurized water reactor nuclear power unit initiating events, it can be seen that the EPR nuclear power unit adds LOCA accidents under states C, D and E compared with other third-generation nuclear power units, including non-isolable small break accidents inside the containment and isolable breaks of the residual heat removal system inside and outside the containment.

[0075] Further, the accident includes non-isolable loss of coolant accident and isolable loss of coolant accident; for the non-isolable small break accident inside the containment of the EPR nuclear power unit under states C, D and E and the break of the residual heat removal system inside and outside the containment, the initiating event frequency can be determined according to the non-isolable LOCA and isolable LOCA accident initiating event analysis method.

[0076] Step S30 includes:

[0077] The frequency analysis of the non-isolable loss of coolant accident and the isolable loss of coolant accident in the corresponding initiating event is performed to obtain the frequency analysis result of the corresponding initiating event.

[0078] The non-isolable loss of coolant accident includes: reactor coolant system pipe rupture and pressurizer safety valve stuck open;

[0079] The isolable loss of coolant accident includes: containment residual heat removal system pipe break and containment residual heat removal system pipe break.

[0080] The obtained pressurized water reactor nuclear power plant shutdown condition safety analysis data is used for this purpose, and the LOCA accident analysis of the EPR nuclear power unit under states C, D and E is as follows:

[0081] (1) Non-isolable LOCA

[0082] A small break loss of coolant accident (SBLOCA) caused by a non-isolable break of the reactor coolant system (RCP) pipe or the emergency boron system (RBS) injection line with an equivalent diameter less than or equal to DN50 (equivalent area less than or equal to 20 cm2) will cause coolant loss and a decrease in the pressure of the reactor coolant system (RCP) in the shutdown condition of the EPR nuclear power unit in the state C, D, E, with the residual heat removal system (RIS) connected in the residual heat removal (RHR) mode.

[0083] The non-isolable LOCA includes: RCP pipe break (to the second valve of the associated system) and small break caused by the opening of the pressurizer safety valve that cannot be closed.

[0084] Among them, the RCP pipe break is represented as: according to the international general data source, the typical frequency value of the PWR small break accident in the power condition is 5E-04 / reactor year. In the shutdown condition, because the stress is low, the frequency of RCP pipe break is lower than that in the power condition. In mode Ca, according to the research, the frequency of LOCA accident of RCP pipe is 1 / 28 of that in the power condition. In states Cb, D, E, the primary circuit is in or close to atmospheric pressure state, and the LOCA accident of the RCP system pipe in these states is less likely to occur, so the frequency of LOCA accident of the primary circuit pipe in the above states is no longer calculated.

[0085] In state Ca, the frequency of LOCA of the primary circuit pipe can be calculated by the following formula 1:

[0086]

[0087] Among them, F A is the frequency of LOCA of the primary circuit pipe in state A; tc a is the operating time of the EPR unit in state Ca; t A is the operating time of the EPR unit in state A.

[0088] According to formula 1, the frequency of RCP small break in state Ca is 1.24E-07 / reactor year, which is calculated by the operating time of the EPR nuclear power unit in each state in Table 1. For states Cb, D and E, stress analysis shows that the RCP is in or close to atmospheric pressure state, and the LOCA accident of the RCP system pipe is less likely to occur.

[0089] EPR nuclear power plant is provided with three relief pipes on the top of the pressurizer, and each pipe is equipped with a safety valve. When the RHR is connected, the pressurizer safety valve provides a one-loop cold overpressure protection to prevent the pressure vessel cylinder from failing due to brittle fracture before reaching the coolant system design pressure at low temperature. When the one-loop pressure exceeds the setting value of the pressurizer safety valve, the pressurizer safety valve will open. If the pressurizer safety valve is stuck in the open position, a one-loop LOCA event will occur through the safety valve. The one-loop coolant will enter the pressurizer relief tank through the pressurizer relief pipe. The temperature, pressure and liquid level indications in the pressurizer relief tank will remind the operator to open the stuck valve, and if the operator closes the stop valve, the LOCA will be terminated.

[0090] The frequency of LOCA caused by the stuck open pressurizer safety valve can be quantified by the Figure 2 event tree. In states C, D and E, after the RHR system is put into operation, the RCP system pressure protection is completed by the RHR safety valve. Before the RHR is connected, the RCP system pressure protection is completed by the pressurizer safety valve. Therefore, only the LOCA caused by the stuck open pressurizer safety valve in state Ca1 needs to be considered.

[0091] In state Ca1, the frequency of accidental opening of one pressurizer safety valve is 1.79E-06 / reactor year, the probability of the pressurizer safety valve being unable to close after opening is 3.5E-05, the probability of the operator not closing the stop valve is taken as 1E-02, and the probability of the stop valve failing to close is 1.51E-05. Therefore, in state Ca1, the frequency of LOCA caused by the stuck open pressurizer safety valve is 1.89E-12 / reactor year.

[0092] (2) Isolable break

[0093] In normal operating states C and D, the plant is cooled by the safety injection and residual heat removal system (RIS) in the residual heat removal (RHR) mode. The one-loop coolant is drawn from the reactor cooling system (RCP) hot pipe section by the low-pressure injection (LHSI) pump, cooled, and finally injected into the RCP cold pipe section. The accident is caused by an isolable break in a RIS line during RHR mode operation, and the break size is less than or equal to DN250. The isolable break inside the containment can be located:

[0094] Downstream of the RIS isolation valve closest to the RCP, on the RIS water suction line connected to the RCP hot pipe section, or upstream of the check valve closest to the RCP, on the RIS injection line connected to the RCP cold pipe section.

[0095] A LOCA is a break that is isolated outside the containment and is caused by a system connected to the RCP system that results in a loss of coolant accident. LOCA accidents are a concern for public health risk because radioactive fission products can bypass the containment structure and be released directly into the environment.

[0096] The breakable breaks considered in the EPR nuclear power plant unit state C, D and E accident analysis include the RHR system pipe break inside the containment and the RHR system pipe break outside the containment. The frequency of the two types of breakable breaks can be calculated according to the RHR system pipe break frequency.

[0097] According to the international data source, the pipe failure frequency data of the commercial nuclear power plant is obtained for use, and the safety-related system pipe break frequency is 1.92E-10 / section*hour. According to the statistics, the RHR system has 42 pipe sections inside the containment and 47 pipe sections outside the containment. Therefore, the frequency of the RHR system break inside the containment is 8.06E-09 / hour, and the frequency of the RHR system break outside the containment is 9.02E-09 / hour.

[0098] According to Table 1, the frequency of the RHR system pipe break inside and outside the containment can be calculated, and the frequency of the RHR system pipe break inside the containment in states C, D and E is respectively: 8.95E-07 / heap year, 3.55E-07 / heap year, 9.75E-07 / heap year. The frequency of the RHR system pipe break outside the containment in states C, D and E is respectively: 1.00E-06 / heap year, 3.95E-07 / heap year, 1.09E-06 / heap year.

[0099] The LOCA caused by the system connected to the RCP system cannot be estimated as a single initiating event to occur, but is evaluated in a series of backgrounds. These events consider the possibility of system high pressure, the possibility of breakage, and the recovery of operators and other factors. It is expected that the frequency of the isolable LOCA of the EPR nuclear power plant unit in states C, D and E will be less than 1E-06 / heap year.

[0100] And in this embodiment, after step S20, further comprising:

[0101] Step S21: analyzing the frequency source of the accident initiating event in the optimization object, if it is judged that the frequency source does not meet the preset standard, then executing step S30.

[0102] In addition, in this embodiment, the frequency source includes: a small break accident inside the containment that cannot be isolated and a breakable break of the residual heat removal system inside and outside the containment;

[0103] Containment inoperable small break accident:

[0104] The EPR nuclear power plant small break accident frequency in state C, D, E is based on the international general data through the calculation of the LOCA frequency value in different states. The LOCA event initiation event frequency value in shutdown condition is mainly given in combination with the pipe size and running time. The temperature and pressure conditions are not considered as variables affecting the accident frequency as the key inducement of pipe break. The calculation of the shutdown break frequency based on the NUREG-5750 database is time-equivalent, and the conservative degree is high.

[0105] The international general data source of the initiation event frequency is used for this. In NUREG-5750, the median value of the small LOCA initiation event frequency in power condition is 5E-04 / year, and the estimated value of the small LOCA initiation event frequency given in the reference plant is less than 5E-04 / year.

[0106] For small LOCA accidents in states C, D and E including boron injection pipes, the initiation event frequency is mainly based on the LOCA frequency value given in NUREG-5750 combined with pipe size and running time. The small LOCA accident initiation event frequency in full power state is 5E-04 / year, and these pipe operating events account for about 1% per year, so the small LOCA frequency of EPR nuclear power plant in states C, D and E is less than or equal to 5E-06 / year. In fact, the small LOCA frequency in states C, D and E will be significantly reduced because the primary loop pressure boundary pressure is greatly reduced compared with the full power state.

[0107] Containment inoperable small break accident:

[0108] The EPR nuclear power plant small break accident frequency in state C, D, E is based on the international general data through the calculation of the LOCA frequency value in different states. The LOCA event initiation event frequency value in shutdown condition is mainly given in combination with the pipe size and running time. The temperature and pressure conditions are not considered as variables affecting the accident frequency as the key inducement of pipe break. The calculation of the shutdown break frequency based on the NUREG-5750 database is time-equivalent, and the conservative degree is high.

[0109] Among them, the accident condition refers to the deviation from the normal operation, which is lower than the expected operation event frequency but more serious. Accident conditions include design basis accidents and (DBC) design extension conditions (DEC). Design basis accidents refer to hypothetical accidents that cause nuclear power plant accident conditions, and the release of radioactive materials in these accidents is within the acceptable limit. Design extension conditions refer to accident conditions not considered in design basis accidents, which should be considered in the design process according to the best estimation method, and the release of radioactive materials in this accident condition is within the acceptable limit. Design extension conditions include conditions without causing significant damage to the core and core melting (severe accident) conditions.

[0110] EPR nuclear power plant selects the following main safety functions according to the potential risk caused by the accident, and selects the corresponding accident as the object of accident analysis: control of reactivity and power, heat removal and radioactive containment in fuel elements.

[0111] According to the annual frequency of accidents, the design basis accidents are divided into four categories of design basis conditions, and the classification criteria of the four categories of DBC accidents are as follows:

[0112] DBC-1: normal operation related transient; DBC-2: expected operation event (10-2 / reactor year < f); DBC-3: rare accident (10-4 / reactor year < f < 10-2 / reactor year); DBC-4: extreme accident (10-6 / reactor year < f < 10-4 / reactor year). Note: f is the frequency of event / accident occurrence.

[0113] According to the state of the accident to the core, the DEC accidents are divided into conditions causing significant damage to the core and core melting (severe accident) conditions:

[0114] DEC-A: design extended condition / over design basis accident without core melting and DEC-B: specified severe accident (SA) leading to core melting.

[0115] The initiating event with a lower frequency than the design basis accident and not as a design basis accident can be a DEC-A (design extended condition without causing significant damage to the core). The frequency of the event is usually less than 10-6 / reactor year, and the event can be classified as a DEC event.

[0116] In this embodiment, combined with the analysis results of the non-isolable LOCA and the isolable LOCA initiating event frequency under states C, D and E, the in-containment non-isolable small break accident of the EPR nuclear power plant under states C, D and E and the out-of-containment residual heat removal system isolable break can be classified as DEC events.

[0117] In this embodiment, according to the analysis results of the LOCA accident initiating event frequency, the LOCA initiating event list is optimized according to the EPR nuclear power plant accident classification standard, and the optimized LOCA accident initiating event list is shown in Table 3.

[0118] Table 3: Optimized LOCA accident initiating event list of EPR nuclear power plant

[0119]

[0120]

[0121] In this embodiment, as Figure 3As shown, the application also constructs an EPR nuclear power unit accident initiating event list optimization system, comprising:

[0122] A collection module is configured to collect the initiating event list of each nuclear power unit;

[0123] A comparison module is configured to compare and analyze each initiating event list, and determine the optimization object of the EPR nuclear power unit accident initiating event list according to the comparison result;

[0124] A frequency analysis module is configured to perform frequency analysis on the accident initiating event in the optimization object;

[0125] A classification module is configured to reclassify the accident in combination with the EPR accident classification standard and the frequency analysis result;

[0126] An optimization module is configured to optimize the initiating event list according to the classification result;

[0127] A result generation module is configured to generate the optimized initiating event list.

[0128] In this embodiment, the collection module is further configured to:

[0129] Obtain the design safety requirements of the EPR nuclear power unit;

[0130] The comparison module is further configured to:

[0131] Divide the operating range of the EPR nuclear power unit into multiple states according to the design safety requirements, compare the initiating event list of the EPR nuclear power unit with the initiating event list of other nuclear power units horizontally, identify the difference items between each initiating event list, and select the corresponding initiating event from the multiple states as the optimization object of the accident initiating event list according to the identification result.

[0132] Specifically, the specific cooperation operation process between each module in the EPR nuclear power unit accident initiating event list optimization system can refer to the above-mentioned EPR nuclear power unit accident initiating event list optimization method, which will not be described here.

[0133] In addition, an electronic device of the present application includes a memory and a processor; the memory is configured to store a computer program; and the processor is configured to execute the computer program to implement the EPR nuclear power unit accident initiating event list optimization method of any one of the above. Specifically, according to the embodiments of the present application, the processes described above with reference to the flowcharts can be implemented as a computer software program. For example, the embodiments of the present application include a computer program product including a computer program carried on a computer readable medium, the computer program including program code for executing the method shown in the flowchart. In such embodiments, the computer program can be downloaded and installed by the electronic device and executed to perform the above-mentioned functions defined in the method of the embodiments of the present application. The electronic device in the present application can be a notebook, desktop, tablet computer, smart phone, etc. terminal, or a server.

[0134] In addition, a storage medium of the present application has a computer program stored thereon, and the computer program is executed by a processor to implement the EPR nuclear power unit accident initiating event list optimization method of any one of the above. Specifically, it should be noted that the storage medium of the present application described above can be a computer readable signal medium or a computer readable storage medium or any combination of the above. The computer readable storage medium may, for example, but is not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or apparatus, or any combination of the above. More specific examples of the computer readable storage medium can include, but are not limited to, an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In the present application, the computer readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, device or apparatus. In the present application, the computer readable signal medium can include a data signal carried in a baseband or as a part of a carrier wave, which carries computer readable program code. Such a propagated data signal can take various forms, including but not limited to an electromagnetic signal, an optical signal or any suitable combination of the above. The computer readable signal medium can also be any computer readable medium other than the computer readable storage medium, which can send, propagate or transmit a program for use by or in conjunction with an instruction execution system, device or apparatus. The program code contained on the computer readable medium can be transmitted by any suitable medium, including but not limited to a wire, a cable, an RF (radio frequency) or the like, or any suitable combination of the above.

[0135] The computer readable medium can be included in the electronic device, or can exist separately from the electronic device.

[0136] The various embodiments described in the specification are progressive in nature, and each embodiment highlights the differences from other embodiments, and the same and similar parts between embodiments can be mutually referred to. For the device disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the method part.

[0137] The skilled person can further realize that the units and algorithm steps of the examples described in combination with the embodiments disclosed herein can be realized by electronic hardware, computer software or a combination of both. In order to clearly illustrate the interchangeability of hardware and software, the components and steps of the examples have been described in the above description in general terms. Whether the functions are realized in hardware or software depends on the specific application and design constraints of the technical solution. The skilled person can use different methods to realize the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0138] The steps of the method or algorithm described in combination with the embodiments disclosed herein can be directly implemented by hardware, a software module executed by a processor, or a combination of both. The software module can be placed in a random access memory (RAM), a memory, a read-only memory (ROM), an electrically programmable ROM, an electrically erasable programmable ROM, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.

[0139] By implementing the present application, the following beneficial effects are achieved:

[0140] The application discloses an EPR nuclear power unit accident initiating event list optimization method and system. By comparing the differences between the EPR nuclear power unit and other nuclear power units, the optimization object of the accident initiating event list is determined first, then the accident initiating event frequency is analyzed to obtain the frequency analysis result, and then the accident is reclassified according to the EPR accident classification standard and the frequency analysis result, and finally the initiating event list is optimized according to the classification result to obtain the optimized initiating event list. After the initiating event list of the EPR nuclear power unit is optimized by the method, the EPR accident analysis and the EPR nuclear power unit operation technical specification are optimized, the unit online maintenance is realized, and the economic benefit of the nuclear power plant is further improved under the premise of ensuring safety.

[0141] It can be understood that the above embodiments only express the preferred embodiments of the present application, the description is more specific and detailed, but it cannot be understood as the limitation of the patent scope of the present application; it should be pointed out that for ordinary skilled in the art, the above technical features can be freely combined without departing from the concept of the present application, and several modifications and improvements can be made, which belong to the protection scope of the present application; therefore, any equivalent transformation and modification made with the patent claim scope of the present application shall belong to the coverage of the patent claim of the present application.

Claims

1. A method for optimizing a list of accident initiating events for an EPR nuclear power plant unit, characterized in that, The method comprises the following steps: Step S10: Collecting an initiating event list of each nuclear power unit; Step S20: Comparatively analyzing each of the initiating event lists by comparing the differences between the EPR nuclear power unit and other nuclear power units, and determining the optimization object of the initiating event list of the EPR nuclear power unit according to the comparison result; Step S30: Frequency analysis on the initiating event in the optimization object; Step S40: Re-classifying the accident in combination with the EPR accident classification standard and the frequency analysis result; Step S50: Optimizing the initiating event list according to the classification result; Step S60: Generating the optimized initiating event list.

2. The EPR nuclear power plant list of accident initiating events optimization method of claim 1, wherein, The step S10 further comprises: Obtaining the design safety requirement of the EPR nuclear power unit; The step S20 further comprises: Dividing the operation range of the EPR nuclear power unit into multiple states according to the design safety requirement, comparing the initiating event list of the EPR nuclear power unit with the initiating event list of other nuclear power units horizontally, identifying the difference items between each of the initiating event lists, and selecting the corresponding initiating event from the multiple states as the optimization object of the initiating event list of the accident according to the identification result.

3. The EPR nuclear power plant set of accident initiating event list optimization method of claim 2, wherein, The accident comprises an unisolable loss of coolant accident and an isolable loss of coolant accident; The step S30 comprises: Frequency analysis on the unisolable loss of coolant accident and the isolable loss of coolant accident in the corresponding initiating event, and obtaining the frequency analysis result of the corresponding initiating event.

4. The EPR nuclear power plant set of accident initiating event list optimization method of claim 3, wherein, The unisolable loss of coolant accident comprises a reactor coolant system pipe rupture and a pressurizer safety valve stuck open; The isolable loss of coolant accident comprises a containment in-vessel residual heat removal system pipe break and a containment out-vessel residual heat removal system pipe break.

5. The EPR nuclear power plant list of accident initiating events optimization method of claim 1, wherein, The step S20 further comprises: Step S21: Analyzing the frequency source of the initiating event of the accident in the optimization object, and executing the step S30 when it is judged that the frequency source does not conform to the preset standard.

6. The EPR nuclear power plant list of accident initiating events optimization method of claim 5, wherein, The frequency source comprises a containment in-vessel unisolable small break accident and a containment in-vessel and out-vessel residual heat removal system isolable break.

7. An EPR nuclear power plant accident initiating event list optimization system, characterized by, The method comprises: A collecting module configured to collect an initiating event list of each nuclear power unit; A comparing module configured to comparatively analyze each of the initiating event lists by comparing the differences between the EPR nuclear power unit and other nuclear power units, and determine the optimization object of the initiating event list of the EPR nuclear power unit according to the comparison result; A frequency analysis module configured to perform frequency analysis on the initiating event in the optimization object; A classifying module configured to re-classify the accident in combination with the EPR accident classification standard and the frequency analysis result; An optimizing module configured to optimize the initiating event list according to the classification result; A result generating module configured to generate the optimized initiating event list.

8. The EPR nuclear power plant unit event list optimization system in accordance with claim 7, wherein, The collecting module is further configured to: Obtain the design safety requirement of the EPR nuclear power unit; The comparing module is further configured to: According to the design safety requirement, the operation range of the EPR nuclear power unit is divided into multiple states, the list of initiating events of the EPR nuclear power unit is compared with the list of initiating events of other nuclear power units, differences between the lists of initiating events are identified, and according to the identification result, a corresponding initiating event is selected from the multiple states as an optimization object of the list of accident initiating events.

9. An electronic device, comprising: Comprise: One or more processors; A storage device for storing one or more programs, when the one or more programs are executed by the one or more processors, the one or more processors implement the EPR nuclear power unit accident initiating event list optimization method as claimed in any one of claims 1-6.

10. A storage medium having stored thereon a computer program, characterized in that The computer program is executed by the processor to implement the EPR nuclear power unit accident initiating event list optimization method as claimed in any one of claims 1-6.

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